static extern void _pickImageFromGallery(
     ImageResultDelegate callback, IntPtr callbackPtr,
     IGUtils.ActionVoidCallbackDelegate cancelCallback, IntPtr cancelPtr,
     int source,
     float compressionQuality,
     bool allowEditing,
     int iPadX, int iPadY);
 static extern void _pickImageFromCamera(
     ImageResultDelegate callback, IntPtr callbackPtr,
     IGUtils.ActionVoidCallbackDelegate cancelCallback, IntPtr cancelPtr,
     float compressionQuality,
     bool allowEditing,
     bool isRearCamera,
     int flashMode);